Making bales with 30 percent of global crop residues — the stalks and such left after harvesting — and then sinking the bales into the deep ocean could reduce the build up of global carbon dioxide in the atmosphere by up to 15 percent a year, according to just published calculations.

That is a significant amount of carbon, the process can be accomplished with existing technology and it can be done year after year, according to Stuart Strand, a University of Washington research professor. Further the technique would sequester — or lock up — the carbon in seafloor sediments and deep ocean waters for thousands of years, he says.